1. Field
The present disclosure relates generally to hearing assistance devices such as, for example, implantable cochlear stimulation (“ICS”) systems and hearing aids.
2. Description of the Related Art
A wide variety of hearing assistance devices are available. Such devices include, but are not limited to, ICS systems and hearing aids.
ICS systems are used to help the profoundly deaf perceive a sensation of sound by directly exciting the auditory nerve with controlled impulses of electrical current. Ambient sound pressure waves are picked up by an externally worn microphone and converted to electrical signals. The electrical signals, in turn, are processed by sound processor circuitry, converted to stimulation data (e.g., a pulse sequence having varying pulse widths and/or amplitudes), and transmitted to an implanted receiver circuit of the ICS system. The implanted receiver circuit is connected to an implantable electrode array that has been inserted into the cochlea of the inner ear, and electrical stimulation current is applied to varying electrode combinations to create a perception of sound. Alternatively, the implantable electrode array may be directly inserted into the cochlear nerve without residing in the cochlea.
ICS systems commonly include an implantable device, an external sound processor, with the sound processor circuitry, and a microphone that is in communication with the sound processor circuitry. In one type of ICS system, the sound processor is worn behind the ear (a “BTE sound processor”). The sound processor transmits stimulation data, as well as power from its battery, to the implantable device by way of an inductive link. To that end, ICS systems include a headpiece that is connected to the sound processor by a cable. The headpiece has a coil antenna that is used to connect to the headpiece (and BTE sound processor by way of the headpiece) to the implantable device via an inductive link. So configured, the BTE sound processor provides sound processing functionality and also provides power for the entire ICS system. A representative ICS system is disclosed in U.S. Pat. No. 5,824,022, which is entitled “Cochlear Stimulation System Employing Behind-The-Ear Sound processor With Remote Control” and incorporated herein by reference in its entirety. Examples of commercially available ICS sound processors include, but are not limited to, the Advanced Bionics™ Harmony™ BTE sound processor. Other ICS systems are configured such that all of the components (e.g., the battery, the microphone, the sound processor, and the coil) are carried within a single headpiece. One example of such a system is disclosed in U.S. Pat. Pub. No. 2010/0046778, which is entitled “Integrated Cochlear Implant Headpiece” and incorporated herein by reference in its entirety.
Hearing aids include a microphone, sound processor circuitry, and a speaker (sometimes referred to as a “receiver”). Here too, ambient sound pressure waves are picked up by the microphone and converted into electrical signals. The electrical signals, in turn, are processed by sound processor circuitry. The processed signals drive the speaker, which delivers amplified (or otherwise processed) sound pressure waves to the ear canal. Exemplary types of hearing aids include, but are not limited to, BTE hearing aids, receiver-in-canal (“RIC”) hearing aids, in-the-canal (“ITC”) hearing aids and completely-in-the-canal (“CIC”) hearing aids. Examples of commercially available hearing aids include, but are not limited to, the Phonak™ Ambra™ hearing aid and the Phonak™ Naida™ hearing aid.
The present inventors have determined that conventional ICS systems are susceptible to improvement. For example, the present inventors have determined that economies of scale and various regulatory issues make hearing aids a more desirable platform for ICS system sound processing than conventional cochlear implant BTE sound processor and body worn sound processors. The present inventors have also determined that some patients find the wire that extends from the sound processor to the headpiece to be undesirable and that some patients would benefit from a sound processor that can be used in an ICS system, but is smaller than those currently available.